Power tube connection structure of power amplifier and power amplifier

ABSTRACT

A power tube connection structure includes a substrate, a printed circuit board, and a power tube, where a through groove allowing the power tube to pass through is cut into the printed circuit board, a mounting groove is cut into the upper surface of the substrate at a location corresponding to the through groove, one end of the power tube extends through the through groove, and is welded onto a bottom face of the mounting groove, the end of the power tube that extends into the mounting groove abuts onto a side wall of the mounting groove close to an output end of the power amplifier, and a solder flux escape channel is made into the side wall of the mounting groove close to the output end of the power amplifier.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2016/073380, filed on Feb. 3, 2016, which claims priority toChinese Patent Application No. 201520112293.2 filed on Feb. 15, 2015.The disclosures of the aforementioned applications are herebyincorporated by reference in their entireties.

TECHNICAL FIELD

The present invention relates to the field of power amplifiertechnologies, and in particular, to a power tube connection structure ofa power amplifier and a power amplifier.

BACKGROUND

Conventional power amplifiers include two types: drop-in poweramplifiers and surface mount power amplifiers. FIG. 1 is a schematicstructural diagram of a drop-in power amplifier in the prior art,including a substrate 01, a printed circuit board 02 covering an uppersurface of the substrate 01, and a power tube 03. A through groove 04allowing the power tube 03 to pass through is cut into the printedcircuit board 02. A mounting groove 05 is cut into the upper surface ofthe substrate 01 at a location that is corresponding to the throughgroove 04. One end of the power tube 03 extends through the throughgroove 04, and is welded onto a bottom face of the mounting groove 05.

To make it convenient for the power tube 03 to pass through the throughgroove 04 and drop in the mounting groove 05, a size of the mountinggroove 05 is 0.25 mm greater than that of the power tube 03 on one side.To improve power amplification consistency, assembly design of a poweramplifier includes the power tube 03 being pushed toward a side of themounting groove that is close to an output end of the power amplifier,to ensure that there is no gap left between the output end of the poweramplifier and a side wall of the mounting groove that is close to theoutput end of the power amplifier. However, there is consequently noescape channel for gas solder flux during reflow soldering, and a soldervoid is formed at the bottom of the power tube 03.

SUMMARY

Embodiments of the present invention provide a power tube connectionstructure of a power amplifier and a power amplifier, to prevent asolder void at the bottom of a power tube.

To achieve the foregoing objective, according to a first aspect, anembodiment of the present invention provides a power tube connectionstructure of a power amplifier, including a substrate, a printed circuitboard covering an upper surface of the substrate, and a power tube,where a through groove allowing the power tube to pass through is cutinto the printed circuit board, a mounting groove is cut into the uppersurface of the substrate at a location that is corresponding to thethrough groove, one end of the power tube extends through the throughgroove, and is welded onto a bottom face of the mounting groove, the endof the power tube that extends into the mounting groove abuts onto aside wall of the mounting groove that is close to an output end of thepower amplifier, and a solder flux escape channel is made into the sidewall of the mounting groove that is close to the output end of the poweramplifier.

In a first possible implementation manner, with reference to the firstaspect, the solder flux escape channel is a first opening made into theside wall of the mounting groove that is close to the output end of thepower amplifier, and there is a gap left between an inner wall of thethrough groove in the printed circuit board and an outer wall of thepower tube.

In a second possible implementation manner, with reference to the firstaspect, the solder flux escape channel is a first opening made into theside wall of the mounting groove that is close to the output end of thepower amplifier, and a second opening is made into the printed circuitboard at a location that is corresponding to the first opening.

In a third possible implementation manner, according to the first or thesecond possible implementation manner, the power tube includes a pinlaid over an upper surface of the printed circuit board, and a throughhole is made into the pin at a location that is corresponding to thefirst opening.

In a fourth possible implementation manner, according to the first orthe second possible implementation manner, the first opening is asemi-circular opening perpendicular to the bottom face of the mountinggroove.

In a fifth possible implementation manner, with reference to the firstaspect, a side push hole perpendicular to the bottom face of themounting groove is made into a side wall of the mounting groove that isclose to an input end.

In a sixth possible implementation manner, with reference to the firstaspect, multiple protruding supports are laid in one plane on the bottomface of the mounting groove, and a height difference between theprotruding supports and the bottom face of the mounting groove is0.1-0.2 mm.

In a seventh possible implementation manner, according to the sixthpossible implementation manner, there are four protruding supports, twoprotruding supports are laid close to the output end of the poweramplifier, and the rest two protruding supports are laid close to aninput end of the power amplifier.

According to the power tube connection structure of a power amplifierprovided in this embodiment of the present invention, a solder fluxescape channel is made into a side wall of a mounting groove that isclose to an output end of a power amplifier, and during welding, gassolder flux can flow out of the power amplifier through the solder fluxescape channel, preventing a solder void from forming at the bottom of apower tube.

According to a second aspect, an embodiment of the present inventionprovides a power amplifier, including the power tube connectionstructure of a power amplifier according to any one of the foregoingtechnical solutions.

According to the power amplifier provided in this embodiment of thepresent invention, a solder flux escape channel is made into a side wallof a mounting groove that is close to an output end of the poweramplifier. During welding, gas solder flux can flow out of the poweramplifier through the solder flux escape channel, preventing a soldervoid from forming at the bottom of a power tube.

BRIEF DESCRIPTION OF DRAWINGS

To describe technical solutions in embodiments of the present inventionor in the prior art more clearly, the following briefly describes theaccompanying drawings for describing the embodiments or the prior art.The accompanying drawings corresponding to the described embodiments ofthe present invention in the following description show merely someembodiments of the present invention, and a person of ordinary skill inthe art may still derive other drawings from these accompanying drawingswithout creative efforts.

FIG. 1 is a schematic structural diagram of a drop-in power amplifier inthe prior art;

FIG. 2 is a schematic diagram of a power tube connection structure of apower amplifier according to an embodiment of the present invention; and

FIG. 3 is a schematic structural diagram of a substrate in a power tubeconnection structure of a power amplifier according to an embodiment ofthe present invention.

DESCRIPTION OF EMBODIMENTS

The following clearly describes technical solutions in embodiments ofthe present invention with reference to the accompanying drawings. Thedescribed embodiments are merely some but not all of the embodiments ofthe present invention. All other embodiments obtained by a person ofordinary skill in the art based on the described embodiments of thepresent invention without creative efforts shall fall within theprotection scope of the present invention.

In the descriptions of the present invention, it should be understoodthat, position or location relationships indicated by the terms“center”, “upper”, “lower”, “ahead”, “behind”, “left”, “right”,“perpendicular”, “horizontal”, “top”, “bottom”, “inner”, “outer”, andthe like are exemplary position or location relationships based on theaccompanying drawings, and are merely intended for ease of describingthe present invention and simplification of description, instead ofindicating or implying that the apparatuses or components referred toneed to be provided in a particular position or be constructed andoperated in a particular position, and therefore, shall not beunderstood as limitations applicable to all embodiments of the presentinvention.

The terms “first” and “second” are merely intended for a purpose ofdescription, and shall not be understood as an indication or implicationof relative importance or an implicit indication of a quantity ofindicated technical features. Therefore, a feature modified by “first”or “second” may explicitly or implicitly include one or more suchfeatures. In the descriptions of the present invention, unless otherwiseindicated, the meaning of “multiple” is two or more.

Referring to FIG. 2, FIG. 2 shows a power tube connection structure of apower amplifier according to an exemplary embodiment of the presentinvention. The power tube connection structure of a power amplifierincludes a substrate 1, a printed circuit board 2 covering an uppersurface of the substrate 1, and a power tube 3. A through groove 21allowing the power tube 3 to pass through is cut into the printedcircuit board 2. A mounting groove 11 is cut into the upper surface ofthe substrate 1 at a location that is corresponding to the throughgroove 21. One end of the power tube 3 extends through the throughgroove 21, and is welded onto a bottom face of the mounting groove 11.The end of the power tube 3 that extends into the mounting groove 11abuts onto a side wall of the mounting groove 11 that is close to anoutput end of the power amplifier. A solder flux escape channel 12 ismade into the side wall of the mounting groove 11 that is close to theoutput end of the power amplifier.

According to the power tube connection structure of a power amplifierprovided in this embodiment of the present invention, a solder fluxescape channel 12 is made into a side wall of a mounting groove 11 thatis close to an output end of the power amplifier. During welding, gassolder flux can flow out of the power amplifier through the solder fluxescape channel 12, preventing a solder void from forming at the bottomof a power tube 3.

In an embodiment of the present invention, the solder flux escapechannel 12 is a first opening made into the side wall of the mountinggroove 11 that is close to the output end of the power amplifier. Forthe convenience of discharge of gas solder flux, there is a gap (notshown in the figure) left between an outer wall of the power tube 3 andan inner wall of the through groove 21 in the printed circuit board 2.Gas solder flux flows into the first opening from the bottom of thepower tube 3, flows from the bottom up in the first opening and flowsout from the top of the first opening, and is discharged out of thepower amplifier through the gap left between the outer wall of the powertube 3 and the inner wall of the through groove 21 in the printedcircuit board 2. This is convenient for discharge of the gas solderflux.

In another embodiment of the present invention, referring to FIG. 2, thesolder flux escape channel 12 is a first opening made into the side wallof the mounting groove 11 that is close to the output end of the poweramplifier. There is no gap left between an outer wall of the power tube3 and an inner wall of the through groove 21 in the printed circuitboard 2, but a second opening 22 is made into the printed circuit board2 at a location that is corresponding to the first opening. In thiscase, gas solder flux flows sequentially from the bottom up through thefirst opening and the second opening 22, and is discharged out of thepower amplifier from the top of the second opening 22.

Referring to FIG. 2, the power tube 3 usually includes a pin 31 laidover an upper surface of the printed circuit board 2, while the pin 31blocks discharge of gas solder flux to a degree. In order that the gassolder flux is discharged more smoothly, a through hole 311 is made intothe pin 31 at a location that is corresponding to the first opening. Inthis way, the blocking effect of the pin 31 on the gas solder flux isreduced, and therefore, discharge of the gas solder flux is smoother.

To reduce difficulty of processing, the first opening is a semi-circularopening perpendicular to the bottom face of the mounting groove 11. Forthe substrate 1, a semi-circular chamfer is usually processed by using amilling technology, and therefore, the semi-circular opening may beprocessed by using the same technology. This reduces processing stepsand therefore reduces the difficulty of processing.

Referring to FIG. 3, to make it convenient to push the power tube 3toward a side of the mounting groove 11 that is close to the output endof the power amplifier, a side push hole 13 perpendicular to the bottomface of the mounting groove 11 is made into a side wall of the mountinggroove 11 that is close to an input end. A cylindrical pin may beinserted into the side push hole 13. As the cylindrical pin is inserted,the cylindrical pin may squeeze an edge of the power tube 3, so that thepower tube 3 moves toward the side of the mounting groove 11 that isclose to the output end of the power amplifier, until there is no gapleft between the output end of the power amplifier and the side wall ofthe mounting groove 11 that is close to the output end of the poweramplifier.

Different materials are used for the substrate 1 and the power tube 3whose thermal expansion rates also vary greatly. As a result, tearing islikely to occur during welding, damaging the materials. Therefore, asshown in FIG. 3, multiple protruding supports 14 are laid in one planeon the bottom face of the mounting groove 11. A height differencebetween the protruding supports 14 and the bottom face of the mountinggroove 11 is 0.1-0.2 mm. The protruding supports 14 provide support forthe power tube 3, making room for distortion buffer between thesubstrate 1 and the power tube 3. This reduces the occurrence oftearing.

To improve welding precision between the substrate 1 and the power tube3, there are four protruding supports 14. Two protruding supports 14 arelaid close to the output end of the power amplifier. The rest twoprotruding supports 14 are laid close to an input end of the poweramplifier. In this way, the power tube 3 and the substrate 1 areparallel to each other, and solder is more evenly fed during welding.Therefore, the welding precision between the substrate 1 and the powertube 3 is improved.

An embodiment of the present invention further provides a poweramplifier, including the power tube connection structure of a poweramplifier according to any one of the foregoing embodiments.

According to the power amplifier provided in this embodiment of thepresent invention, a solder flux escape channel 12 is made into a sidewall of a mounting groove 11 that is close to an output end of the poweramplifier. During welding, gas solder flux can flow out of the poweramplifier through the solder flux escape channel 12, preventing a soldervoid from forming at the bottom of a power tube 3.

Other components and the like of the power amplifier in this embodimentof the present invention are well known to a person skilled in the art,and details are not described herein.

The foregoing descriptions are merely specific implementation manners ofthe present invention, but are not intended to limit the protectionscope of the present invention. Any variation or replacement readilyfigured out by a person skilled in the art within the technical scopedisclosed in the present invention shall fall within the protectionscope of the present invention. Therefore, the protection scope of thepresent invention shall be subject to the protection scope of theclaims. Additionally, statements made herein characterizing theinvention refer to an embodiment of the invention and not necessarilyall embodiments.

What is claimed is:
 1. A power tube connection structure of a poweramplifier, comprising: a substrate; a printed circuit board covering anupper surface of the substrate; and a power tube; wherein the printedcircuit board comprises a through groove configured to allow the powertube to pass through; wherein the substrate comprises a mounting groovecut into the upper surface of the substrate at a location thatcorresponds to the through groove; wherein one end of the power tubeextends through the through groove, is welded to a bottom face of themounting groove, and abuts a side wall of the mounting groove; whereinthe mounting groove comprises a solder flux escape channel disposed inthe side wall of the mounting groove; wherein the solder flux escapechannel comprises a first opening disposed in the side wall of themounting groove; wherein there is a gap between an inner wall of thethrough groove in the printed circuit board and an outer wall of thepower tube; wherein the first opening is a semi-circular openingperpendicular to the bottom face of the mounting groove.
 2. The powertube connection structure according to claim 1, wherein the power tubecomprises a pin disposed over an upper surface of the printed circuitboard, and the pin comprises a through hole at a location thatcorresponds to the first opening.
 3. The power tube connection structureaccording to claim 1, wherein the printed circuit board comprises asecond opening at a location that corresponds to the first opening. 4.The power tube connection structure according to claim 3, wherein thepower tube comprises a pin disposed over an upper surface of the printedcircuit board, and the pin comprises a through hole at a location thatcorresponds to the first opening.
 5. The power tube connection structureaccording to claim 1, wherein the side wall of the mounting groovecomprises a side push hole perpendicular to the bottom face of themounting groove.
 6. The power tube connection structure according toclaim 1, further comprising: multiple protruding supports disposed inone plane on the bottom face of the mounting groove, wherein a heightdifference between the protruding supports and the bottom face of themounting groove is in the range of 0.1-0.2 mm.
 7. The power tubeconnection structure according to claim 6, wherein the multipleprotruding supports comprise four protruding supports, wherein twoprotruding supports of the four protruding supports are disposed at alocation corresponding to an output end of the power amplifier, and theother two protruding supports of the four protruding supports aredisposed at a location corresponding to an input end of the poweramplifier.
 8. A power amplifier, comprising a power tube connectionstructure, the power tube connection structure comprising: a substrate;a printed circuit board covering an upper surface of the substrate; anda power tube; wherein the printed circuit board comprises a throughgroove configured to allow the power tube to pass through; wherein thesubstrate comprises a mounting groove cut into the upper surface of thesubstrate at a location that corresponds to the through groove; whereinone end of the power tube extends through the through groove, is weldedto a bottom face of the mounting groove, and abuts a side wall of themounting groove; wherein the mounting groove comprises a solder fluxescape channel disposed in the side wall of the mounting groove; whereinthe solder flux escape channel comprises a first opening disposed in theside wall of the mounting groove; wherein there is a gap between aninner wall of the through groove in the printed circuit board and anouter wall of the power tube; wherein the first opening is asemi-circular opening perpendicular to the bottom face of the mountinggroove.
 9. The power amplifier according to claim 8, wherein the powertube comprises a pin disposed over an upper surface of the printedcircuit board, and the pin comprises a through hole at a location thatcorresponds to the first opening.
 10. The power amplifier according toclaim 8, wherein the printed circuit board comprises a second opening ata location that corresponds to the first opening.
 11. The poweramplifier according to claim 10, wherein the power tube comprises a pindisposed over an upper surface of the printed circuit board, and the pincomprises a through hole at a location that corresponds to the firstopening.
 12. The power amplifier according to claim 8, wherein the sidewall of the mounting groove comprises a side push hole perpendicular tothe bottom face of the mounting groove.
 13. The power amplifieraccording to claim 8, wherein the power tube connection structurefurther comprises: multiple protruding supports disposed in one plane onthe bottom face of the mounting groove, wherein a height differencebetween the protruding supports and the bottom face of the mountinggroove is in the range of 0.1-0.2 mm.
 14. The power amplifier accordingto claim 13, wherein the multiple protruding supports comprise fourprotruding supports, wherein two protruding supports of the fourprotruding supports are disposed at a location corresponding to anoutput end of the power amplifier, and the other two protruding supportsof the four protruding supports are disposed at a location correspondingto an input end of the power amplifier.